Modification of commercial poly-lactide for extrusion coated food packaging applications

Poly-L-lactide (PLLA) is a widely used sustainable and biodegradable alternative to replace synthetic non-degradable plastic materials in the packaging industry. Conversely, its processing properties are not always optimal, e.g. insufficient melt strength at higher temperatures (necessary in extrusion coating processes). This thesis reports on research to improve properties of commercial PLLA grade (3051D from NatureWorks), to satisfy and extend end-use applications, such as food packaging by blending with modified PLLA. Adjustment of the processability by chain branching of commercial poly-L-lactide initiated by peroxide was evaluated. Several well-defined branched structures with four arms (sPLLA) were synthesized using pentaerythritol as a tetra-functional initiator. Finally, several block copolymers consisting of polyethylene glycol and PLLA (i.e. PEGLA) were produced to obtain a well extruded material with improved heat sealing properties. Reactive extrusion of poly-L-lactide was carried out in the presence of 0.1, 0.3 and 0.5 wt% of various peroxides [tert-butyl-peroxybenzoate (TBPB), 2,5-dimethyl-2,5-(tert-butylperoxy)-hexane (Lupersol 101; LOL1) and benzoyl peroxide (BPO)] at 190C. The peroxide-treated PLLAs showed increased complex viscosity and storage modulus at lower frequencies, indicating the formation of branched/cross linked architectures. The material property changes were dependent on the peroxide, and the used peroxide concentration. Gel fraction analysis showed that the peroxides, afforded different gel contents, and especially 0.5 wt% peroxide, produced both an extremely high molar mass, and a cross linked structure, not perhaps well suited for e.g. further use in a blending step. The thermal behavior was somewhat unexpected as the materials prepared with 0.5 wt% peroxide showed the highest ability for crystallization and cold crystallization, despite substantial cross linking. The peroxide-modified PLLA, i.e. PLLA melt extruded with 0.3 wt% of TBPB and LOL1 and 0.5 wt% BPO was added to linear PLLA in ratios of 5, 15 and 30 wt%. All blends showed increased zero shear viscosity, elastic nature (storage modulus) and shear sensitivity. All blends remained amorphous, though the ability of annealing was improved slightly. Extrusion coating on paperboard was conducted with PLLA, and peroxide-modified PLLA blends (90:10). All blends were processable, but only PLLA with 0.3 wt% of LOL1 afforded a smooth high quality surface with improved line speed. Adhesion levels between fiber and plastic, as well as heat seal performance were marginally reduced compared with pure 3051D. The water vapor transmission measurements (WVTR) of the blends containing LOL1 showed acceptable levels, only slightly lower than for comparable PLLA 3051D. A series of four-arm star-shaped poly-L-lactide (sPLLA) with different branch length was synthesized by ring opening polymerization (ROP) of L-lactide using pentaerythritol as initiator and stannous octoate as catalyst. The star-shaped polymers were further blended with its linear resin and studied for their melt flow and thermal properties. Blends containing 30 wt% of sPLLA with low molecular weight (30 wt%; Mwtotal: 2500 g mol-1 and 15000 g mol-1) showed lower zero shear viscosity and significantly increased shear thinning, while at the same time slightly increased crystallization of the blend. However, the amount of crystallization increased significantly with the higher molecular weight sPLLA, therefore the star-shaped structure may play a role as nucleating agent. PLLA-polyethylene glycol–PLLA triblock copolymers (PEGLA) with different PLLA block length were synthesized and their applicability as blends with linear PLLA (3051D NatureWorks) was investigated with the intention of improving heat-seal and adhesion properties of extrusion-coated paperboard. PLLA-PEG-PLLA was obtained by ring opening polymerization (ROP) of L-lactide using PEG (molecular weight 6000 g mol-1) as an initiator, and stannous octoate as catalyst. The structures of the PEGLAs were characterized by proton nuclear magnetic resonance spectroscopy (1H-NMR). The melt flow and thermal properties of all PEGLAs and their blends were evaluated using dynamic rheology, and differential scanning calorimeter (DSC). All blends containing 30 wt% of PEGLAs showed slightly higher zero shear viscosity, higher shear thinning and increased melt elasticity (based on tan delta). Nevertheless, no significant changes in thermal properties were distinguished. High molecular weight PEGLAs were used in extrusion coating line with 3051D without problems.

Structural dynamics in the global pulp and paper industry

The pulp and paper industry is currently facing broad structural changes due to global shifts in demand and supply. These changes have significant impacts on national economies worldwide. Planted forests (especially eucalyptus) and recovered paper have quickly increased their importance as raw material for paper and paperboard production. Although advances in information and communication technologies could reduce the demand for communication papers, and the growth of paper consumption has indeed flattened in developed economies, particularly in North America and Western Europe, the consumption is increasing on a global scale. Moreover, the focal point of production and consumption is moving from the Western world to the rapidly growing markets of Southeast Asia. This study analyzes how the so-called megatrends (globalization, technological development, and increasing environmental awareness) affect the pulp and paper industry’s external environment, and seeks reliable ways to incorporate the impact of the megatrends on the models concerning the demand, trade, and use of paper and pulp. The study expands current research in several directions and points of view, for example, by applying and incorporating several quantitative methods and different models. As a result, the thesis makes a significant contribution to better understand and measure the impacts of structural changes on the pulp and paper industry. It also provides some managerial and policy implications.

Vaakatasossa toimivan modulaarisen pakkausyksikön prässin suunnittelu kartonkipakkauksille

Kartonkivuokien käyttö elintarviketeollisuudessa on kasvanut vuosi vuodelta ja kuluttajat ovat löytäneet kartonkipakkaukset niiden ekologisuuden, graafisen ulkoasun sekä turvallisuuden ansiosta. Vuokien valmistus mekaanisella prässäyksellä kehittyy jatkuvasti ja uusi teknologia mahdollistaa täysin uudentyyppisten prässien valmistuksen. Työn tavoitteena on tutkia voidaanko mekaaninen prässäys toteuttaa vaakatasossa uutta teknologiaa hyödyntämällä kustannustehokkaasti. Lisäksi tavoitteena on selvittää, millä voimantuottomenetelmällä prässiltä vaadittava voimantuotto on edullisinta toteuttaa. Suunnittelussa otetaan huomioon olemassa olevat työkalut, modulaarisuus, EU:n elintarvikelainsäädäntö sekä muut kriittiset tekijät. Työssä sovelletaan metodisen konstruoinnin mukaisesti systemaattista ongelmanratkaisua (VDI 2221). Lisäksi työssä käydään läpi kilpaileva menetelmä arvoanalyysi. Suunnittelua ja komponenttivalintoja analysoidaan SWOT- sekä pisteanalyysien avulla. Suunnittelussa syntyneiden ratkaisujen lujuusominaisuuksia tarkastellaan FEM-analyysillä. Tuloksista havaittiin, että vaakatasossa suoritettava prässäyksen voimantuotto on edullisinta ja yksinkertaisinta toteuttaa sähkömekaniikalla, että halutut ominaisuudet voidaan saavuttaa ja rakenne pitää mahdollisimman kompaktina. Kustannustehokkuuden saavuttamiseksi hankinnat on syytä kilpailuttaa huolellisesti. Työn lopussa esitetään mahdollisia jatkokehityskohteita, joita syntyi tämän diplomityön aikana.

Factors Affecting Runnability of Press Forming Equipment

The growth of the food packaging industry has raised more interest in bio-based fibre packing. The use of petroleum based packages is unfriendly to the environment while bio-based is a sustainable option for food packing. In this Master Thesis the aim was to discover how the press forming machineries runnability is affected by parameters of the press and how it also affects formability of paperboard trays. Familiarisation of the working operation parameters was done with the KAMA ST 75 flat-bed die cutting machine and the VP3-70 mould press. Some small test runs of moulding trays where done to get acquainted to the adjustment parameters of the machines. Literature study was done on how paperboards physical properties react to the forces applied during press forming. The study of what kind of defects to the paperboard tray might occur during forming process and the causes for these defects. Also how the parameters of the press forming machine affects formability of the tray. Maintenance procedures was done to the press forming machine to enhance the reliably of production process. Tool alignment measurement was done to determine proper alignment. Laboratory test of the physical properties of the test material was done to find any connection to how the test material performs in press forming. An evaluation criterion was made to evaluate the dimensions and defects of the tray. From the test result a conclusion can be drawn on how the parameters of the press forming process affect the paperboard material. Based on the results the adjustment the parameters of moulding machines to the mechanical properties of paperboard it is possible to produce high quality fibre passed trays for the food packaging industry.

Ontario Forest Industries Association records, 1900-1989, n.d.

The Ontario Forest Industries Association (OFIA) was founded in 1944. It is a provincial trade association that represents member companies who produce a wide range of products, including pulp, paper, paperboard, lumber, panelboard, plywood and veneer. The OFIA works with its member companies to address issues of common interest and concern, and communicates these issues to the appropriate government, industrial or business sector. The Ontario Forest Information Service represented the OFIA from 1951 to 1988 as the publishers of their industry periodicals. Bush News was the first periodical published by the Service for the OFIA and ran until 1964, when it was replaced by Ontario Logger. In 1968, the name was changed to The Logger. In 1970, this was replaced by The Forest Scene. This new periodical was a departure from the earlier versions, which had served primarily as an internal communication system for the industry. The Forest Scene adopted a new format and editorial approach, emphasizing outdoor activities, recreation, hunting and fishing, conservation, and forestry operations and methods, thus appealing to a much wider readership. The Forest Scene ceased publication in 1988.

Perfil Logístico de Colombia; Sector Papel y Cartón

Actualmente en Colombia no se realizan los suficientes estudios logísticos para analizar aspectos importantes y relevantes de cada uno de los sectores del país, esto se debe en parte a la limitada tecnología e información que poseen cada uno de estos, este es el motivo por el cual se realizará una investigación sobre el perfil logístico del sector de fabricación de papel y cartón, con el fin de mejorar la información pertinente y así ayudar tanto al país como a las empresas que se desenvuelven en este entorno, para que de esta manera logren solucionar los problemas que se puedan presentar en cuanto a la implementación logística y así llegar a obtener mejoras y ayudar a la productividad y competitividad de Colombia. Se escogió este sector debido a que este es uno de los destacados a nivel país y con potencial de crecimiento a corto plazo, ya que realiza aportes a las actividades económicas, la productividad y competitividad de Colombia en proporciones de gran escala. Este sector pertenece al código CIIU 210 según la clasificación del “código industrial internacional uniforme” siendo uno de los más competitivos del país. Por otro lado se realizará un análisis del sector en el mundo para así lograr identificar problemas y oportunidades en el país para incrementar su eficiencia en diferentes aspectos logísticos como el transporte, almacenamiento, tiempos de producción, entre otros. Para esto se tendrán en cuenta diversas variables como la balanza comercial, el Producto Interno Bruto y la productividad que tiene actualmente el país.

Influence of package, type of apple juice and temperature on the production of patulin by Byssochlamys nivea and Byssochlamys fulva

Although the production of patulin in apple fruits is mainly by Penicillium expansum, there is no information on the ability of heat resistant moulds that may survive pasteurization to produce this mycotoxin in juice packages during storage and distribution. In this study, the production of patulin by Byssochlamys spp (Byssochlamys nivea FRR 4421, B. nivea ATCC 24008 and Byssochlamys fulva IOC 4518) in cloudy and clarified apple juices packaged in laminated paperboard packages or in polyethylene terephthalate bottles (PET) and stored at both 21 degrees C and 30 degrees C, was investigated. The three Byssochlamys strains were able to produce patulin in both cloudy and clarified apple juices. Overall, the lower the storage temperature, the lower the patulin levels and mycelium dry weight in the apple juices (p<0.05). The greatest variations in pH and degrees Brix were observed in the juices from which the greatest mycelium dry weights were recovered. The maximum levels of patulin recovered from the juices were ca. 150 mu g/kg at 21 degrees C and 220 mu g/kg at 30 degrees C. HPLC-UV, HPCL-DAD and mass spectrometry analyses confirmed the ability of B. fulva IOC 4518 to produce patulin. Due to the heat resistance of B. nivea and B. fulva and their ability to produce patulin either in PET bottles or in laminated paperboard packages, the control of contamination and the incidence of these fungi should be a matter of concern for food safety. Control measures taken by juice industries must also focus on controlling the ascospores of heat resistant moulds. (C) 2010 Elsevier B.V. All rights reserved.

Flerskiktat papper : en sammanställning av historia, teknik och forskningsresultat

Until the beginning of the 1900:th century the paper making process was handicraft. The paper machines that have been developed since then are as impressing in size as fascinating when it comes to the technique. The process has always been improved to give a better paper for lower costs, with as short manufacture time as possible. Stratified forming has been a reality since 1830. From the beginning it was applied to board and paperboard. Now it is also the most common method for making tissue and one paper mill in Austria use it for fine paper. Stratified forming can be categorized as separate forming or simultaneous forming. Separate forming means using several headboxes and sometimes even several wires. Simultaneous forming means using only one stratified headbox. This method has many advantages over separate forming, inter alia improved economy, quality, wood exchange and higher runability of the paper machine. Several experiments have been done with simultaneous forming of different fibres by placing a fibre with high bulk in the middle layer and a smooth fibre on the surface layers. The results has shown that by using this method both the bending stiffness and surface properties are improved, or a lower grammage paper is obtained with maintaining quality. Simultaneous forming can also be used to stratify fillers in layers where they are most efficient. In that way both paper quality and economy is improved. Simultaneous forming is also used for fractionated pulp. Fractionation means separating springwood fibre from summerwood fibre, and placing them in separate layers. Research results of fractionated pulp show about the same result as simultaneous forming of different fibres.

Optiska egenskapers påverkanav möjligheten att trycka eftermålvärden i ISO 12647-2.

This thesis investigates how the optical properties of paperboard influences printing with targets in ISO 12647-2. The targets for optical properties in ISO 12647-2 are defined for paperboard without optical brightening agents and fluorescent brightening agents wich makes it difficult to reach the targets when printing paperboard containing these agents.Seven different types of paperboard, some with and some without the agents, have been printed and instrumentally andvisually measured to see if there is any deviation from the standard targets and if it shows visually.The result shows that paperboard containing optical brightening agents and fluorescent brightening agents can print with targets in ISO 12647-2 but in many measurments the difference between the types of paperboard were to small to assess. The differences between the types of paperboard in the instrumental measurements did not fully correspond with the waythe panel appraised them visually.

Da cartolina ao computador: uma proposta para o estudo de Geometria

Pós-graduação em Educação Matemática - IGCE

Commission of Noah Cooke, Jr., as chaplain in the Continental Army, signed by John Hancock, 1776 January 1

Commission of Noah Cooke, Jr., as chaplain in the Continental Army, signed by John Hancock, 1 January 1776.

1987 census of manufactures.

Mode of access: Internet.

1987 census of manufactures.

Mode of access: Internet.

1987 census of manufactures.

Mode of access: Internet.

1992 census of manufactures.

Mode of access: Internet.